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991.
T. R. Allen J. I. Cole E. A. Kenik H. Tsai S. Ukai S. Mizuta T. Yoshitake 《JOM Journal of the Minerals, Metals and Materials Society》1999,51(10):27-30
An understanding of the effects of long-term, low-dose-rate radiation on core components is critical to light-water reactor
plant life extension. Following reactor shutdown, materials that had experienced long exposures to low-dose-rate irradiation
were retrieved from the EBR-II research reactor for analysis. These components are being analyzed to provide insight into
pressurized water reactor life extension. In this work, three examples of EBR-II materials analyses are highlighted: radiation-induced
segregation in 304 stainless steel, stress relaxation in Inconel X750, and swelling in 316 stainless steel.
For more information, contact T.R. Allen, Argonne National Laboratory-West, P.O. Box 2528, Idaho Falls, Idaho 83403-2528;(208)533-7760;
fax (208) 533-7863; e-mail todd.allen@anlw.anl.gov. 相似文献
992.
Bor-Yuan Tsai Simon Stobart Norman Parrington Ian Mitchell 《Annals of Software Engineering》1999,8(1-4):203-221
Extensive test data is required to demonstrate that “few” errors exist in software. If the process of software testing could
be carried out automatically, testing efficiency would increase and the cost of software development would be significantly
reduced. In this paper, a tool for detecting errors in object oriented classes is proposed. The approach uses a state-based
testing method. The method utilises state machines in order to produce threaded multi-way trees, which are referred to as
inspection trees. Inspection trees can be used to generate test cases and parse test results files. This allows us to determine
whether the classes under test contain errors. The algorithms for the creation of inspection trees and the examination of
the test results file using an inspection tree are described in the paper.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
993.
Jing‐Fu Dai Chia‐Cherng Chang Jia‐Wen Lee Szu‐Ju Li Yao‐Tsung Tsai 《International Journal of Numerical Modelling》2004,17(5):421-432
In this paper, we study the decoupled method which requires less memory on semiconductor device simulation. The decoupled method decouples the three equivalent circuits of semiconductor and solves them sequentially. The three equivalent circuits are formed by formulating the three partial differential equations that describe the electrical behaviour of semiconductor. Since the decoupled method solves one equation in each stage, the decoupled method uses one‐ninth memory space of the coupled method. When decoupling the three equivalent circuits, the decoupled method yields a boundary condition limitation. In order to overcome the limitation, we propose a compromising partial decoupled method which has complete boundary condition and requires four‐ninth memory space of the coupled method. The three methods are compared for computational efficiency and accuracy in the simulation of BJT. The simulation results are identical. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
994.
1,5-Bis(4-trimellitimido)naphthalene (II) was prepared by the condensation reaction of 1,5-naphthalenediamine and trimellitic anhydride. A series of aromatic poly(amide-imide)s
(IV
a–o) was synthesized by the direct polycondensation of the diimide-diacid (II) and various aromatic diamines (III
a–o). The reaction utilized triphenyl phosphite and pyridine as condensing agents in the presence of calcium chloride in N-methyl-2-pyrrolidone (NMP). The inherent viscosities of the resulting poly(amide-imide)s were in the range of 0.55∼1.39 dL/g.
These polymers were generally soluble in polar solvents, such as N,N-dimethylacetamide (DMAc), NMP, N,N-dimethylformamide (DMF). Flexible and tough poly(amide-imide) films were obtained by casting from a DMAc solution and had
tensile strengths of 90∼145 MPa, elongations to break of 5∼13 %, and initial moduli of 2.29∼3.73 GPa. The glass transition
temperatures of some poly(amide-imide)s were recorded in the range of 206∼218 °C, and most of the polymers did not show discernible
glass transition on their DSC traces. The 10% weight loss temperatures were above 522 °C in nitrogen and above 474 °C in air
atmosphere. 相似文献
995.
A CO2 laser with cylindrical focal lens has been used to glaze the surface layer of plasma-sprayed ZrO2-20wt% Y2O3/MCrAlY coatings. Both a continuous-wave laser and a pulsed laser were used in this study. Different parameter settings for
power, travel speed, and pulse frequency were used, and their effects on the melting width, melting depth, coupling efficiency,
microstructure, surface roughness, and process defects have been evaluated. Results show that the melting width of the glazed
track was slightly smaller than the diameter of the raw beam. The melting depth increased with increasing energy density for
both a continuous-wave laser and a pulsed laser. The coupling efficiency as about 40 to 65% for a continuous-wave laser, which
increased with increasing laser travel speed, but decreased with an increase in energy density. The power density has no significant
effect on coupling efficiency. Defects, such as bubbles or depressions, occur easily with a continuous wave laser. A high-quality
glazed layer is successfully produced using a pulsed laser. The surface roughness of the plasma-sprayed ceramic coatings was
significantly improved by laser glazing. Surface roughness decreased slightly as the pulse frequency increased for the glazed
surface. Based on this study, proper processing parameters have been suggested. 相似文献
996.
In this paper, we derive a time-complexity bound for the gradient projection method for optimal routing in data networks. This result shows that the gradient projection algorithm of Goldstein-Levitin-Poljak type formulated by Bertsekas (1982), Bertsekas and Gallager (1987) and Bertsekas et al. (1984) converges to within ε in relative accuracy in O(ε-2hminNmax) number of iterations, where Nmax is the number of paths sharing the maximally shared link, and hmin is the diameter of the network. Based on this complexity result, we also show that the one-source-at-a-time update policy has a complexity bound which is O(n) times smaller than that of the all-at-a-time update policy, where n is the number of nodes in the network. The result of this paper argues for constructing networks with low diameter for the purpose of reducing complexity of the network control algorithms. The result also implies that parallelizing the optimal routing algorithm over the network nodes is beneficial 相似文献
997.
Embedding of any type of data in images based on a human visual model and multiple-based number conversion 总被引:2,自引:0,他引:2
A novel approach to embedding any type of digital data into a cover image is proposed, which utilizes a human visual model to guarantee that the modification of the cover image is imperceptible. A quantized contrast function based on the model is constructed first. The gray values of each 3×3 sub-image of the cover image are used to compute, using the function, a range of gray levels with the same contrast as that of the central pixel of the sub-image. The embedding process proceeds by replacing the gray value of the central pixel by one of the values in the range. This guarantees that the changes be imperceptible. The data to be embedded is treated as a binary stream and is partitioned into a number of sub-streams. A multiple-base number conversion mechanism is used to convert each sub-stream of data into values which are then embedded in the central pixels of sub-images. The embedded data can be extracted out from the resulting stego-image without referencing the original image. Experimental results show that the proposed method is feasible. 相似文献
998.
Ya-Yun Hsiao Fang-Hsin Chen Chun-Chieh Chan Ching-Chih Tsai 《International journal of molecular sciences》2021,22(21)
This paper estimates the yields of DNA double-strand breaks (DSBs) induced by ultrasoft X-rays and uses the DSB yields and the repair outcomes to evaluate the relative biological effectiveness (RBE) of ultrasoft X-rays. We simulated the yields of DSB induction and predicted them in the presence and absence of oxygen, using a Monte Carlo damage simulation (MCDS) software, to calculate the RBE. Monte Carlo excision repair (MCER) simulations were also performed to calculate the repair outcomes (correct repairs, mutations, and DSB conversions). Compared to 60Co γ-rays, the RBE values for ultrasoft X-rays (titanium K-shell, aluminum K-shell, copper L-shell, and carbon K-shell) for DSB induction were respectively 1.3, 1.9, 2.3, and 2.6 under aerobic conditions and 1.3, 2.1, 2.5, and 2.9 under a hypoxic condition (2% O2). The RBE values for enzymatic DSBs were 1.6, 2.1, 2.3, and 2.4, respectively, indicating that the enzymatic DSB yields are comparable to the yields of DSB induction. The synergistic effects of DSB induction and enzymatic DSB formation further facilitate cell killing and the advantage in cancer treatment. 相似文献
999.
1000.
Ching-Hao Chen Chun-Hou Liao Kuo-Chiang Chen Kuan-Lin Wang Xiao-Wen Tseng Wei-Kung Tsai Han-Sun Chiang Yi-No Wu 《International journal of molecular sciences》2021,22(21)
Interstitial cystitis (IC) is a chronic inflammatory disease characterized by bladder pain and increased urinary frequency. Although the C57BL/6J (B6) and FVB/NJ (FVB) mouse strains are commonly used as animal models for studies involving the urinary system, few reports have compared their lower urinary tract anatomy, despite the importance of such data. Our study aimed to characterize bladder function changes in FVB and B6 mouse strains with lipopolysaccharide (LPS)-induced IC, to understand mouse model-based bladder research. The bladder function parameters were measured by cystometrogram. Histological assay was examined by hematoxylin and eosin stain, Masson’s trichrome stain, and immunofluorescence staining. Results indicated that the two strains in the control group exhibited different bladder structures and functions, with significant anatomical differences, including a larger bladder size in the FVB than in the B6 strain. Furthermore, cystometry tests revealed differences in bladder function pressure. LPS-treated B6 mice presented significant changes in peak pressure, with decreased intercontraction intervals; these results were similar to symptoms of IC in humans. Each strain displayed distinct characteristics, emphasizing the care required in choosing the appropriate strain for bladder-model studies. The results suggested that the B6 mouse strain is more suitable for IC models. 相似文献